Telephone-exchange line switch



June 2, 1925} 1,540,034

' C. D. RICHARD TELEPHONE EXCHANGE LINE SWITCH Filed Sepc- 1920 I 2 Sheets-S/heet 1 //4 van for; (ha/46's 0. Richard June 9 1,540,034

- c. D. RICHARD I TELEPHONE momma. LINE swI'rcn Filed Sept. 5, 1920 2 Sheets- Sheet 2 F74. Z.

. V /M van fon (ha/46's 0. Richard.

Patented June 2, 1925.

UNITED STATES PATENT OFFICE.

CHARLES DONAT RICHARD, OF NEW BRIGHTON, NEXV YORK, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE LINE SW'I'ICH.

Application filed September 3, 1920.

T ml? whom it may concern:

Be it known that I, CHAnLns D. RICHARD,

'a citizen of France, residing at New Brighton, in the county of Richmond, State of New York, have invented certain new and useful Improvements .in Telephone- Exchange Line Switches, of which the following is a full, clear, concise, and exact description;

This invention relates to automatic telephone exchange switching apparatus and more especially to line switches of the nonnmnerical type for automatically connecting subscribers lines to idletrunks, whereby :alls are extended to other switching apparatus which operates to connect calling subscribers lines to the called lines.

Heretofore one of the obstacles to. uninterrupted service which has had to be contended with in automatic telephone systems employing line switches, has been due to the difficulty encountered and excessive time re quired in removing and replacingindividual sets or units of bank terminals when trouble develops therein. This difficulty has been due, most particularly, to the large number of wires required for connecting to the large number of subscribers line bank terminals and the trunk terminals associated therewith.

One object of the present invention is, therefore, to overcome, as far as possible, the delays incidental to repairs on the terminal banks and this object is 'accon'iplished in large measure by the arrangement of banks set forth and described hereinafter.

(Jo-incidental with the problem of provid ing a suitable terminal bank to overcome the difficulty before stated,there was the problem of providing an operating mechanism adapted to co-operate with the new arrangement of banks. The provision of such a mechanism is, therefore, the second object of the present invention.

Inaccordance with the above objects, one feature of theinventionconsists in arranging the banks in four sections, each comprising a plurality of sets of contact springs arranged in a straight row. The four sections being grouped in parallel quadrangular relation, one to the other, about an oper- Serial No. 407,959.

' ating mechanism whichis accessible to every also results in a much smaller structure for r a given number of lines accommodated than has been practicable heretofore, on account of the fact that the operating mechanism employed therewith is greatly simplified.

.Other features of this invention reside in the unique mechanism whereby the contact springs are operated to effect connections between subscribers lines and trunk lines. One of the latterfeatures consists in the provision, for each set of contact springs, of an operating lever or bell crank adapted to slide on a guide member over the several spring pi1e-ups in its respective sets of con tactsprings and in combination therewith of an electromagnetic device particularly adapted to operate the plunger in all of its positions. Another feature of the operatingmechanism resides in the combination with the operating levers, of two notched bars 7 arranged to slide longitudinally and adapted to engage, by means of their notches, all the idle operating levers and move them simulbeing broken away to facilitate illustration: Fig. 2, is an end view showing the step-by step driving mechanism whereby the contact operating devices are shifted from position p a view of the switch in elevation, some parts to position, relative"to-their several asso- I ciated sets of contacts; and Fig. Sis a section taken along the line 3, 3 of Fig. 1, illustrating the arrangement of the devices and the relative arrangement thereto, of the contact operating mechanism.

The base 1, together with end plates 2 and groups of contact springs, each mounted in opposed parallel relation to the other. Each group comprises two strips of contact springs l, 5 and 6, 7 respectively, and each strip comprises a bar '9 on each of which are mounted a plurality of sets of contact springs, each set comprising subscribers line springs and trunk springs. Bars 9 are each attached by means of screws 8 to the end plates 2 and 3 whereby they are supported. The connecting wires for each strip of contact springs are run in an individual cable 10 to a terminal block 12 comprising terminals 11 and screws 13. The cable terminals at the terminal block; ends are each provided with a punching 37 adapted to be inserted under the heads of screws 13.

His clearly evident then that in the event of trouble many of the contactspr'ings, the strip in which the troubleis located may be quickly removed simply by loosening screws 13 of the terminal block associated with that strip and removing screws 8. A not-herstrip of contact springs together with the cable may then be substituted for the faulty strip, the entire operation co-nsuming but a small period of time. Traffic on the other three strips ofthe bank is not interfered within the least, during the time that the faulty strip is being removed and replaced by another.

Grdinarily, line switches. are adapted to accommodate 100 subscri ers linesand 10 trunk lines,-this proportion being subject to change to meet different traflic require ments. In the present description, it is pre sumed that 10 trunks are to be provided.

Referring to Fig. 1, it will be seen that the contact springs of each strip arearranged in groups of ten sets each. Each of these groups of ten sets of contact springs is associated with one subscribers line, that is, the tensets of springs are multiply connected to the same line. Each set of springs in a group is connected to a different trunk. Each trunk is connected to one set of springs in every snbscribers group. The subscribers line springs and tr'unk springs are normally out of contact.

There is provided for each subscribers group of contact springs-an operating-bell crank 18, each of which is mounted on a stationary rod 19, and adapted to slide thereon longitudinally of its strip of contact springs into operable relation with its sew eral associated sets of contact springs individua'lly.

Two parallel bars, and 21 are each provided with a plurality of notches 22. one notch for each bell crank 18. Tiese bars are mounted on the end plates 2 and 3 and in all of its several POSltl-ODS and which is adapted to slide thereon in a. direction long-L tudinal of the strips of contact springs. Each bar 29 and 21 is provided with a follower which engages grooved path on contact springs.

rotation of 'shaft uand cam 24.

Bell cranks 18 normally engage notches 22 and ar movedfrom position to position relative to their several associated. sets-0f contact springs by bar-s20 and 21.

Mounted on end plate 2, concentric with shaft'25 1s a commutator,comprising 1O stationary contact terminals each insulated from the other and from the end plate 2.

Thesestationary' terminals are each ,asso- 1 ciated with one of the ten trunks leading into the switch. A -br ush "37 'insu latively mounted on shaft and rotatable therewithis-adapted to wipe overstationary contacts 35. The switch is so designed that brush 37 isalways in contact with that terminal 85 which is associated'with the trunkwhich 1s connected -to thesets' of contact springs before 'wlnchthe normal' bell cranks are'situated. Stationaryterminals-35 are associated with the energizing circuit ofelectromagnet in such a way-that t'he magnet is energized "whenever brush 3'7 makes contact withn terminal associated with a busy trunk. "Each :timeelectromagnet '30 is energized it rotates'shaft 25 together with cam 24 and brush 37 t-liroughan angleof 36, that is,one tenth-of -'a circle and accordingly steps brush 37 to the next succeeding terminal Rotation of cam 2% through one step is iustsn-fficient to :move the normal bell cranks from one position to the next, relative to their severahsets of.

So long as brush 3? continues to -make contact with stationary terminals 35 which are associated with busy trunks, electromagnet O wi-lleontinue stepping ratchet wheel 27 around. WVl-ienbrush 37 is finally brought into engagement with a stationary terminal 35 associ-ated with an i-dle'trunk, the circuit of electromagnet 30 is broken and the mechanismis brought to a standstill. All the normal bel l-=cranks are then positioned before the sets of contact 1 I trunks.

For eachbell-crank there is provided an electromagnet 14, each of which has an armature 17 which engages the bell crank.

adapted to engage the bell crank upon the energization of the electromagnet to effect the operation of the contact springs. Electromagnets 14 are each associated with a subscribers lines and are operable upon the initiation of calls on their respective lines. The electromagnets 14 are mounted on bars which eXtend between end plates 2 and 3 and which are provided with angle members 16, whereby they are attached to the end plates.

Upon the initiation of a call on a subscribers line, electromagnet 14 associated therewith is energized and draws up its armature 17. Armature 17 engaging bell crank 18, rotates the latter about rod 19, causing an arm thereof to engage and operate the set of contact springs before which it is, at the time, situated. The other arm of the bell crank which is normally connected with its notch 22 in one of the sliding bars 20 or 21 is withdrawn therefrom. Operation of the contact springs established a connection between the calling subscribers line and a trunk and further established an energizing circuit from electromagnet whereupon the latter draws up its armature 29 which steps ratchet wheel 27, shaft 25, brush 37 and cam 24 forward one step. All the normal bell cranks are thereby moved to their next succeeding position. If the trunk connected withthe contact springs in the latter position is idle, the aforementioned mechanism will stop, but if the trunk should be busy, electromagnet 30 will again be energized to step the mechanism to the next posit-ion, and so forth, until a position associated with an idle trunk is found.

Two plates 32 and 33'are provided with notches on their two edges for engaging the bell cranks in their operated positions and prevent further longitudinal displacement thereof until they again engage their notches in bars 20 and 21. Inasmuch as the bars 20 and 21 are moved immediatel after the initiation of a call, the notches 22 are usually not in line with their respective bell cranks when the latter are released at the termination of the call. 'The locking plates 32 and 33 continue to engage the bell cranks until they actually drop into their notches in the bar, thus preventing the bell cranks being moved by the frictional engagement of the bars therewith.

Referring to Fig. 3, the two upper bell cranks are seen to be engaging their notches in bar 20 in which position they are adapted to move with the bar. The bell crank in the lower left-hand position is seen to be disengaged from its notches in bar 21 and enga ed by one of the notches in looking plate The armature 17 associated with the latter bell crank is in normal position, the call having terminated. which resulted in the releasing of the bell crank. lVhen the bar 21 is moved sufliciently the latter bell crank automatically drops into its associated notch 22 and remains in operable relation tion on opposite sides of said operating mechanism. I

2. In a switching mechanism, a bank of operable terminal contacts, a duplex operating mechanism for said contacts, said bank comprising two groups of strips of movable contacts, each group comprising two strips,

each of said strips comprising a plurality of sets of said contacts and each strip in each group occupying an identical angular position, and the two groups arranged in parallel relation in opposite sides of said operating mechanism.

In a switching mechanism, a plurality of sets of contacts arranged in rows, aduplex-mechanism for operating said contacts comprising a plurality of stationary bars, a plurality of operable members arranged on each of said bars, means for driving said members in a movement axially along said bars, means for operatively engaging said members, said means when operated being effective to cause interengagement between said contacts.

4. In a switching mechanism, a plurality of sets of contact springs situated in a row, an operating bell crank for said contact springs arranged to slide forward and back longitudinally of said row and adapted to be positioned in operable relation to the several sets of contact springs individually, a member adapted to engage said'bell crank when the latter is in normal position and move therewith longitudinally of said row of contact springs, an electromagnet, an armature for said electromagnet operable to disengage said bell crank from said member and to engage said bell crank with any said sets of contact springs individually, a locking device provided with a plurality of notches, one for each set of contact springs, said notches adapted to engage said bell crank when the latter is engaged with any of said sets of contact springs, and prevent further longitudinal movement thereof until said bell crank is again engaged by said member, driving means for said member, and means for controlling the said driving means.

p 5. In a switching mechanism, a plurality of sets of contact" springs situated in a row, an operating bell. crank forsaid contact springs arranged to slide forward and back operation of longitudinally of said row andadapted-rho be positioned ii-roperable relation to the several sets of contact springs individually, one arm or said bell crank being arranged to engage and operate sai-d contact springs,

na-lly of said row, an electromagnet, an

armature for said 'electron'iagnet operable to move said bell crank, upon energization of said electromagnet,.to disengage it from the notch in said notched bar and to engage it with any of said sets of contact springs before which it may be positioned to effect operation of said contact springs, a notchedpiate adaptedto engage said bell crankwhen operated .in'any of its ,positionsand prevent further longitudinal movement thereof nntil said-bell crank isagain engaged by thenotch in said bar, drivingmeans for said notched bar, and means 'Eor controlling the operation of said driving means. i

6. In a line switch, an operating mechanism, two parallel groups o'E'oontactspr-ings, situatedon opposite sides of said ope 'ating mechanism, line conductors andtrnnk conductors multiply connected with said contactsprings, operating levcrsladapted to be moved from position to position relative to said contact springs, a notched bar adapted to'engage and move said operating. levers intotheir several operative positions relative to said contact springs, electromagnetic means responsive to calls initiated. on said line conductors for operating said operating lovers to eliect operation of said contact springs, and means for restraining said operating levers from further displacement. when operated and thereafter until said operating levers areiagain engagedby said notches, means for driving said bar, and means for selecting idle trunks.

7. Ina line switch, an operating mechanism, two parallelgronps of. contact springs situated on opposite sides of said operating mechanism, each group comprising 1 two strips of contact springs and each strip comprising a plurality of sets of contact springs situated in a row on a common plane, the

two strips in each group being arranged on a common frame butindividually removable therefrom, said operating mechanism com prising a bell crank for each set of said contacts and each adapted to be moved from.

position to position relative to the several sets of contact springs in their respective strips, a pair of bars arranged in parallel relation to each other, notches in said bars, one for each bell crank, whereby said bell cranks are engaged when not'operated and caused to move with said bars, means for reciprocating said bars loingitudinallyv of said "strips, electromagnetic :means to disengage said (bell-cranks. from their respective notches in saidbars rand to engage said bell cranks with said contact springsto effect operation rther-eof, agpair of notched .plates, one tor each group of contact sprmgspeach adapted 4 to engage the bell cranks associated .With their respect-iveigrou-ps when operated to engage said contact springs and to restrain said bell craniks. from further .dlsp'laceni ent long tudinally of their respective rows of contact springs until ,sai'di bell cranks are again engaged-by the notches-in theirrespective bars.

8. Ina line switch, a supporting member,

two parallel bars slidably mounted. .on said supportln-ganeinber, a rotatable scam adapted torecipi ocate said bars 1 simultaneously in opposite directions, notches in each of said bars, bell cranks .slidableinma direction parallel to .said bars-,saidgbel l cranks each normally engaging one of said notches, and movableby said bars when so engaged, electromagnetic inea-ns for rotating said cam, a terminal bank operably associated with said bell cranks, said terminal bank comprising a iilurality of sets of .contactsprings, a locking plate provided with plurality of notches, one for each .set of; contact springs, said lockingplate adapted to ngage said bell cranks, whenlthe latter :areoperated to engage said A contact. springs, "and prevent further ,displ aceinent of said bell cranks: by

said bars i-intilusaid bell cranksare again engaged-bythe :notches in said bars, and a second electromagnetic means operable to move said bell cranksto engage and operate saidncontact springs andto: disengage the notches in said bars 9. Ina telephone-.excl1.an1ge, a group of subscribers lines, a grou-p of trunk lines, .a terminal bank for saidlines in which each of .saidwsnbscri bers. lines is associatedwith eachof .said trunk lines, said terminal bank comprising ,{two parallel groups 'of contact springs situated in opposing relation one to the. other, :eachgroup comprisingtwo parallelstrips of contact springs, and-eacli strip coin-prising aiplnrality of sets of contact springs situated in a row on a common plane, each of said subscribers lines connected to a consecutive series oi sets of contact springs in one. of said strips, and eachoi said trunk lines connected to a different set ot each subscribers setsv of. contact springs, a plurality of'bell eranksnonewtor each subscriber-7s line, marten cranks adapted to be moved into operable relation I with each I of its associatedsets of contact springs, .a pair of nOtched ba-rs, eaclrada-ptedlo engage by its notches, .amplurality of said bell cranks when the latter. are non-operated,means for reciprocating said bars {together .with the bell :cranks engaged therewith ina direction parallel to .saidstripsof contact springs, a plurality of electroinagnets, one for each bell crank, an armature for each electromagnet, said armatures adapted to operate their associated bell cranks to effect operationv of said contact springs to connect said subscribers lines and trunk lines, and to disengage said hell cranks from the notches in said bars, a pair of locking plates, each as sociated with one of said groups of contact springs, operable to engage said bell cranks When operated and to prevent displacement 10 my name this 27th day of August A. 1)., 15

CHARLES DONAT RICHARD. 

